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111.
Background: Increased serum neuron-specific enolase (NSE) level was found in a substantial proportion (30–69%) of patients with non-small-cell lung cancer (NSCLC), but little was known about the clinical properties of NSE in NSCLC.Objective: We aimed to assess the level of serum NSE to predict prognosis and treatment response in patients with advanced or metastatic non-neuroendocrine NSCLC.Methods: We retrospectively analyzed 363 patients with advanced and metastatic NSCLC between January 2011 and October 2016. The serum NSE level was measured before initiation of treatment.Results: Patients with high NSE level (≥26.1 ng/ml) showed significantly shorter progression-free survival (PFS) (5.69 vs 8.09 months; P=0.02) and significantly shorter overall survival (OS) than patients with low NSE level (11.41 vs 24.31 months; P=0.01).NSE level was an independent prognostic factor for short PFS (univariate analysis, hazard ratio [HR] = 2.40 (1.71–3.38), P<0.001; multivariate analysis, [HR] = 1.81 (1.28–2.56), P=0.001) and OS (univariate analysis, [HR] = 2.40 (1.71–3.37), P<0.001; multivariate analysis, [HR] = 1.76 (1.24–2.50), P=0.002).Conclusion: The survival of NSCLC patients with high serum NSE level was shorter than that of NSCLC patients with low serum NSE levels. Serum NSE level was a predictor of treatment response and an independent prognostic factor.  相似文献   
112.
OVCA1, a tumor suppressor gene, is deleted or lower expressed in about 80% of ovarian cancer. Over expression of OVCA1 in human ovarian cancer A2780 cells inhibits cell proliferation and arrests cells in G1 stage. However, the fact that the molecular mechanism of OVCA1 inhibits cell growth is presently elusive. Here we investigated the potential signaling pathway induced by over-expression of OVCA1. Our results show that over-expression of human OVCA1 in ovarian cancer cells A2780 leads to down-regulation of cyclin D1, and up-regulation of p16, but no effect on the expression of NF-κB. It indicates that OVCA1 could inhibit the proliferation of ovarian cancer cell A2780 by p16/cyclin D1 pathway, but not by NF-κB.  相似文献   
113.
Host cellular receptors play key roles in the determination of virus tropism and pathogenesis.However,little is known about SARS-CoV-2 host receptors with the e...  相似文献   
114.
亚热带红壤区森林土壤剖面微生物残体碳分布及影响因素   总被引:1,自引:0,他引:1  
土壤剖面中20cm以下土壤有机碳(SOC)储量占土壤剖面总SOC储量50%左右,由于土壤微生物残体碳(MRC)是稳定土壤碳库的重要来源,因此研究土壤剖面中MRC对SOC的贡献对于评估土壤碳储量具有重要意义。然而,目前关于MRC含量及其对SOC贡献的研究多数集中在土壤表层,在土壤剖面和母质中尚不清楚。选取江西省千烟洲亚热带典型森林红壤剖面,通过氨基糖与磷脂脂肪酸(PLFA)微生物标志物分析方法,分析红壤剖面和母质中MRC的影响机制及其对SOC贡献的分布特征。研究结果表明:(1)MRC含量随着土壤剖面深度增加而显著降低(P<0.05),在整个土壤剖面中,细菌MRC对SOC贡献为6%—12%,真菌MRC对SOC贡献为12%—36%,MRC对SOC贡献为18%—46%。从土壤表层至母质,真菌MRC对SOC贡献高于细菌MRC。(2)结构方程模型结果表明,在土壤剖面中,MRC含量主要受到微生物-PLFA含量、容重和溶解态有机碳含量的影响。研究量化了红壤剖面中MRC对SOC的贡献,表明在20cm以下土壤及母质中,微生物残体碳对红壤地区生态系统碳库具有重要贡献。  相似文献   
115.
王欣禹  周勇  任安芝  高玉葆 《生态学报》2014,34(23):6789-6796
以感染内生真菌的天然禾草羊草为实验材料,通过体外纯培养条件下的内生真菌、感染内生真菌的离体叶片和在体叶片对3种病原菌的抑菌实验,以探讨内生真菌对宿主植物羊草在抗病性方面的贡献。结果表明:体外纯培养条件下,分离自羊草的内生真菌Epichlobromicola对新月弯孢(Curvularia lunata)、根腐离蠕孢(Bipolaris sorokiniana)和枝孢霉(Cladosporium sp.)这3种病原菌都具有抑制作用,抑菌率分别达56.22%,46.93%和45.15%,且内生真菌培养滤液可以有效抑制这3种病原菌的孢子萌发,平均萌发率分别为30.4%,15.7%和16.4%;宿主植物叶片在离体条件下,内生真菌感染可以有效降低羊草叶片受C.lunata和C.sp.侵染后的病斑数或病斑长度,但对B.sorokiniana不起作用,甚至提高了叶片的病斑数及病斑长度,而离体叶片提取液对不同病原菌均有不同程度的抑制作用;在体条件下,内生真菌均可以通过降低叶片病斑数来增强羊草植株对这3种病原菌的抗性。由此看来,内生真菌E.bromicola对宿主植物羊草在抗病原菌侵染方面有一定的增益作用。  相似文献   
116.
117.

Introduction

Interleukin (IL)-33 is a proinflammatory cytokine contributing to the pathogenesis of rheumatoid arthritis (RA). The gene encoding IL-33 may serve as a genetic factor and be associated with the risk of RA. To investigate the potential association between IL33 and RA, we performed a case–control study based on Chinese Han population.

Methods

A three-stage case–control study was performed. Two tag single-nucleotide polymorphisms (SNPs) (rs7044343 and rs10975514), mapping to the IL33 gene, were first genotyped in the discovery population. We further genotyped rs7044343 and rs10975514 in the validation and replication population. The associations between the two tag SNPs and phenotypic subgroups of RA and levels of serum IL-33 were assessed with a logistic regression model.

Results

In the discovery population, the CC genotype of rs7044343 was associated with RA patients (odds ratio (OR) = 0.777, 95% confidence interval (CI), 0.611 to 0.988; P = 0.040). After anti-citrullinated peptide antibody (ACPA) stratification, the CC genotype of rs7044343 was also shown to be a protective genotype in RA without ACPA (OR = 0.610; 95% CI, 0.379 to 0.982; P = 0.042). In the validation population and replication population, the association between rs7044343 and RA, especially ACPA-negative RA, was still significant. A meta-analysis of discovery, validation, and replication panels confirmed the association between CC genotype of rs7044343 and RA (Pcombined = 0.0004; ORcombined = 0.77; 95% CI, 0.67 to 0.89). No evidence was found for heterogeneity between three sample sets (Phet = 0.99; I2 = 0%). Similar results were also obtained in ACPA-negative RA (Pcombined = 0.0002; ORcombined = 0.57; 95% CI, 0.43 to 0.77). No association was detected between rs10975514 polymorphism and RA susceptibility in the discovery and validation population. The serum levels of IL-33 were significantly lower in the patients with the rs7044343 CC genotype.

Conclusion

The CC genotype of rs7044343 in IL33 is associated with RA patients and downregulates IL-33 expression in RA.  相似文献   
118.

Background

Whether patients with resectable colorectal liver metastases (CRLM) receive survival benefit from neoadjuvant chemotherapy remains controversial.

Methods

We retrospectively analyzed 466 patients with resectable CRLM between 2000 and 2010. Patient characteristics and survival data were recorded.

Results

The patients were divided into one group with neoadjuvant chemotherapy (group NC, n = 121) and another without (group WN, n = 345). There was no difference in 5-year survival (52% vs. 48%) between the two groups. No significant differences were identified between the two groups in terms of 30-day mortality (1.7% vs. 1.2%) or morbidity (33.9% vs. 25.8%). A primary tumor at stage T4, ≥4 liver metastases, the largest liver metastasis ≥5 cm in diameter, and a serum CEA level ≥5 ng/ml were independent prognostic factors. By assigning one point to each, the patients were divided into a low-risk group (0–2) and a high-risk (3–4). The patients in the low-risk group received no survival benefit from neoadjuvant chemotherapy, whereas those in the high-risk group received survival benefit (5-year survival, 39% vs. 33%, P = 0.028).

Conclusions

Preoperative neoadjuvant chemotherapy did not increase mortality or complications. Not all resectable patients, only those with >2 independent risk factors, received survival benefit from neoadjuvant chemotherapy.  相似文献   
119.

Purpose

To investigate the associations of single nucleotide polymorphisms (SNPs) of three genes (IL-12B, IL-12Rβ1 and IL-12Rβ2) in Behcet''s disease (BD) and Vogt-Koyanagi-Harada (VKH) syndrome in a Chinese Han population.

Methods

A total of 806 BD cases, 820 VKH patients, and 1600 healthy controls were involved in this study. The first investigation included 400 BD patients, 400 VKH cases, and 600 healthy individuals. A second confirmatory study included a separate set of 406 BD patients, 420 VKH cases and another 1000 normal controls. Genotyping was carried out by PCR-restriction fragment length polymorphism assay and results were validated by using direct sequencing. The χ2 test was performed to compare the allele and genotype frequencies between cases and healthy controls.

Results

This study comprised two phases. In the first phase study, a significantly increased frequency of the rs3212227/IL-12B genotype CC and C allele was found in BD patients as compared to controls (Bonferroni corrected p value (pc) = 0.009, OR 1.8; pc = 0.024, OR 1.3, respectively). Moreover, the frequency of the C allele of rs3212227/IL-12B was also significantly increased in VKH patients (pc = 0.012, OR 1.3, 95% CI 1.1 to 1.6). No associations were found for the other seven tested SNPs either in BD or VKH disease. The second study as well as the combined data confirmed the significant association of rs3212227/IL-12B with BD (CC genotype: combined pc = 6.3×10−7, OR = 1.8; C allele: combined pc = 2.0×10−5, OR = 1.3, respectively) and the C allele frequency of rs3212227/IL-12B as the risk factor to VKH patients (combined pc = 2.5×10−5, OR 1.3, 95% CI 1.2 to 1.5).

Conclusions

Our study revealed that the IL-12B gene is involved both in the susceptibility to BD as well as VKH syndrome.  相似文献   
120.
Benign adult familial myoclonic epilepsy (BAFME) has been mapped to chromosome 8q23.3–q24.1, 2p11.1–q12.1, 5p15.31–p15.1, and 3q26.32–3q28, in Japanese, Italian, Thai, and French pedigrees, respectively. Recently, we investigated a Chinese BAFME family. Clinical and electrophysiological studies revealed that nine individuals were affected with BAFME. We aimed to establish the causative gene for this pedigree. We genotyped 17 microsatellite markers covering the four previously identified chromosome regions and performed linkage analyses. The linkage analysis data showed that the LOD score was 2.80 for D5S486 at no recombination. This suggested linkage to 5p15.31–p15.1 and excluded linkage to the other three loci (LOD score <0 at no recombination). Our study suggests that the causative gene responsible for BAFME in the Chinese pedigree may be located on chromosome 5p15.31–p15.1.  相似文献   
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